Evaluation of Patients Hospitalized Due to Bleeding Complications Associated with Warfarin Treatment

Abstract

The most significant complication of warfarin therapy is bleeding. The disadvantages of warfarin include its narrow therapeutic range and drug-drug interactions. This study aimed to determine the severity of bleeding events associated with warfarin treatment, mortality, and factors that may influence these outcomes. A total of 119 patients hospitalized due to bleeding complications associated with warfarin use between January 2007 and December 2010 were included in the study. Demographic and clinical data—including age, gender, comorbidities, International Normalized Ratio (INR), and mortality—were analyzed. Bleeding severity was classified according to the Fihn criteria as minor bleeding and major bleeding (severe, life-threatening and fatal bleeding). Fifty-six patients (51.4%) were female,53 (48.6%) were male, and 53.2% of the patients were aged 65 years and older. Hypertension (50.5%) and diabetes mellitus (22.0%) were the most common comorbid conditions. The primary indications for warfarin use were atrial fibrillation (35.8%), followed by cardiovascular diseases (32.1%), history of stroke (26.6%), and prosthetic heart valve (22.0%). The most common presenting symptoms were ecchymosis and upper gastrointestinal bleeding. Major bleeding was significantly more common in males (p=0.046). Ninety-eight percent (n=107) of patients experiencing bleeding had supratherapeutic INR values. Mortality was significantly higher in patients aged 65 years and older (p=0.029). There was no significant difference between genders in terms of overall bleeding event frequency and mortality. In conclusion, advanced age and labile INR are significant factors in warfarin-related bleeding events. Mortality due to warfarin-related bleeding is significantly higher in older patients.

Keywords

• oral anticoagulant therapy
• warfarin
• bleeding
• haemorrhage

Varfarin Tedavisine Bağlı Kanama Komplikasyonları Nedeniyle Hastaneye Yatırılan Hastaların Değerlendirilmesi

Abstract

Varfarin tedavisinin en önemli komplikasyonu kanamadır. Varfarinin, terapötik aralığının dar olması ve ilaç-ilaç etkileşimleri dezavantajları arasında yer almaktadır. Çalışmada varfarin tedavisine bağlı kanama olaylarının şiddeti, mortalite ve etki edebilecek faktörlerin belirlenmesi amaçlandı. Ocak 2007-Aralık 2010 tarihleri arasında varfarin kullanımına bağlı kanama nedeniyle hastaneye yatırılan 109 hasta dahil edildi. Demografik ve klinik özellikler -yaş, cinsiyet, eşlik eden hastalıklar, INR düzeyi ve mortalite- analiz edildi. Kanama şiddeti Fihn kriterlerine göre minör kanama ve major kanama (ciddi, hayatı tehdit edici ve fatal kanama) olarak sınıflandırıldı. Hastaların; 56’sı kadın (%51,4), 53’ü (%48,6) erkek, %53,2’si 65 yaş ve üzerindeydi. Komorbid hastalıklar içinde birinci sıklıkta hipertansiyon (%50,5), ikinci sıklıkta diabetes mellitus (%22,0) saptandı. Varfarin kullanım endikasyonları arasında en sık atriyal fibrilasyon (%35,8), sonrasında kardiyovasküler hastalıklar (%32,1), geçirilmiş stroke (%26,6) ve prostetik kalp kapağı (%22,0) gelmekte idi. En sık geliş semptomu ekimoz ve üst gastrointestinal kanama idi. Majör kanama erkek cinsiyette anlamlı şekilde yüksekti (p=0,046). Kanama geçiren hastaların %98’i (n=107) supraterapötik INR değerine sahipti. Mortalite ileri yaş (≥65 yaş) hastalarda anlamlı şekilde yüksekti (p=0,029). Genel kanama olaylarının sıklığı ve mortalite açısından her iki cinsiyet arasında fark yoktu. Sonuç olarak ileri yaş ve labil INR varfarin ilişkili kanama olaylarında etkilidir. Varfarine bağlı kanama olaylarında mortalite ileri yaş hastalarda anlamlı şekilde daha yüksektir.

Keywords

• oral antikoagülan tedavi
• warfarin
• kanama
• hemoraji

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